Saliva samples used to detect ovulation/fertility?

[Jasper]

It's amazing what you can find on the net.

It's a device called the fertility lens into which you dab some saliva and look at the dried pattern through a lens to see if you are in your fertile phase or not(allegedly)

Anyone ever come across this before?

doula.ws/ovu-tec/

Yes I've seen them on the net - I think babystart.co.uk sell them too - not tried one tho!